Process for manufacturing hollow building plates from ceramic material



H. HARKORT Nov. 13, 1934.

EROQESS FOR MANUFACTURING HOLLOW BUILDING PLATES FROM CERAMIC MATERIALFiled Nov. 14, 1932 In venror;

m/(off 1 WWW 9? Patented Nov. 13, 1934 PROCESS FOR MANUFACTURING HOLLOWBUILDING PLATES FROM/I CERAMIC MA- I TERKAL Hermann Harkort,Berlin-Tegel, Germany Application November 14, 1932, Serial No. 642,623In Germany June 27, 1931 1 Claim.

My present invention relates to a process for manufacturing buildingparts, in particular plates of ceramic material for inside and outsidelining, as iiooring, as protecting layer and such like pur- POSGS.

In order to meet the change of shape, so called shrinkage, during thedrying and burning process the plates with reinforcing ribs on the rearside are manufactured as so called splitting plates by means of asuitable extrusion press provided with a mou hpiece, i. e. double-strongplates with inner hollow spaces shaped in one line side by side. Afterthe burning of the double plate the intermediate walls of the hollowspaces are separated, so that two uniformly shaped plates are formedwhich carry ribs on the one side.

According to my invention the manufacturing proceeds without extrusionpresses in such a manner, that in the principal periods of the manufac 3Luring, i. e. during the drying and burning process,

ing, usual pressing or casting, such as hollow bricks, i. e. the innerspaces are shaped in manufacturing double plates by means of cores whichare removed afterwards.

The annexed drawing shows in Fig. 1 the plaster mold in which theceramic material is shaped,

ig. 2 the splitting plate after being taken out of the mold,

Fig. 3 said plate after the cores being taken out,

Fig. 4 a single plate obtained by splitting the hollow plate after theburning process,

Fig. 5 an inflammable case provided to receive a core member.

In executing my invention by way of shaping the process is as follows:Double plates 1) with hollow spaces passing throughout and splittableintermediate walls (1 are shaped in plaster molds a. The hollow spacesare shaped in such a manner, that flat-shaped cores 6 are molded within,which are supported on both their ends in cavities and drawn out at acertain state of the drying process.

In order to obtain the hollow spaces it may be suitable to use elasticor shrinking cores which may be taken out of the drying or dried hollow1 out.

plate in a pressed condition or owing to their own shrinkage. Furthercores may be used, which are consumed during the burning process of theceramic material. Also fire-proof cores surrounded with an inflammablecase may be used in such a manner that the core pieces are removedduring the drying process and the cases are destroyed by the burningprocess of the hollow body in the ceramic furnace.

The plate b provided with hollow spaces (Fig. 3) after the cores beingtaken out is burnt in the ceramic furnace and then separated bysplitting the intermediate walls d in two uniformly shaped plates 9/(Fig. 4). Said plates carry on the one side ribs h which are shaped bythe separated intermediate walls cl.

In order to facilitate the splitting the intermediate walls are alreadyslightly slotted when the hollow plates b are shaped. For this purposemandrels i are arranged on the one end at both sides of the cores c,said mandrels produce the slots is into the walls d when the cores e aredrawn If split or two-parted hollow bodies of sheet iron as cores areused, they are provided at both sides with thin longitudinal edges whichpenetrate into the intermediate walls d, when the sheet iron parts areforced apart under the pressure of the drying material, whereby thesmall slots are produced. In using fire proof cores surrounded with aninflammable case m (Fig. l.

5) the same is provided with projecting longitudinal edges 1 so as toproduce the small slots into the intermediate walls.

Instead of molding the plates according to the present invention theymay be manufactured in such a manner, that the cores destined for theshaping of the hollow plates are surrounded with the ceramic material bypressing or casting the latter.

My invention enables also the manufacturing of plate-shaped bodies whichhave two or more lines of hollow spaces arranged in layers above eachother and after being split three or more single plates are produced insuch a manner,

that the plates taken from the outside carry ribs on one side and theremaining inner plate shows ribs on both sides. For the forming orshaping of the hollow spaces my invention allows the largest scope,specially in using inflammable cores. So it is possible to shape tworectangular intersecting lines of parallel hollow spaces with theresult, that after splitting instead of ribs only rectangularprojections on the single plates are formed. Also a single hollow spacepassing throughout the double plate may be arranged by I forming a plateof card-board or such like within the mold in such a manner, that onlytwo parallel walls on both sides of the double plate remain andconsequently the single plates obtained by splitting show only twolateral ribs.

What I claim is:

A method of making plates of plastic ceramic material, consisting inpacking the material in a mold around a plurality of cores spaced apartand extending through the recess of the mold to separate the interior ofthe packed material into strips integral with the mass of the materialconstituting the sides of the block, drying the packed ribs extendingalong one of its faces and the other face having a smooth surface.

HERMANN HARKORT.

